Departamento de Engenharia Química, Universidade Tecnológica Federal Do Paraná, Rua Doutor Washington Subtil Chueire, 330, Ponta Grossa, PR 84017-220, Brazil E-mail:
Departamento de Engenharia Química, Universidade Estadual de Maringá, 5790 Colombo Avenue, Maringá, Paraná, 87020-900, Brazil.
Water Sci Technol. 2021 Nov;84(9):2158-2179. doi: 10.2166/wst.2021.409.
In the present work, the performance of Ag/ZnO/CoFeO magnetic photocatalysts in the photocatalytic degradation of ibuprofen (IBP) was evaluated. This study considered the use of pure Ag/ZnO (5% Ag) and also the use of the Ag/ZnO/CoFeO magnetic catalysts containing different amounts (5, 10 and 15% wt) of cobalt ferrite (CoFeO). The catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoacoustic spectroscopy. To carry out the photocatalytic degradation reaction, different concentrations of the ibuprofen contaminant solution (10, 20 and 30 ppm) and different concentrations of photocatalyst were tested (0.3 g L, 0.5 g L and 1.0 g L). The reaction parameters studied were: IBP concentration, catalyst concentration, adsorption and photolysis, influence of the matrix, radiation source (solar and artificial) and the effect of organic additive. At the end of the photocatalytic tests, the best operating conditions were defined. Considering the obtained results of degradation efficiency and magnetic separation, the optimal parameters selected to proceed with the other tests of the study were: ibuprofen solution concentration 10 ppm, Ag/ZnO/CoFeO (5%) catalyst at a concentration of 0.3 g L and pH 4.5 of the reaction medium. The results indicated the feasibility of magnetic separation of the synthesized catalysts. A long duration test indicated that the catalyst exhibits stability throughout the degradation reaction, as more than 80% of IBP was degraded after 300 minutes. The photocatalytic activity was directly affected by the ferrite load. The higher the nominal load of ferrite, the lower the performance in IBP degradation. It was also observed that the smallest amount of ferrite studied was enough for the catalyst to be recovered and reused. The adsorption and photolysis tests did not show significant results in the IBP degradation. In addition, it was possible to verify that the aqueous matrix, the use of solar radiation and the addition of additive (acid formic) were interfered directly in the process. The catalyst reuse tests indicated that it can be recovered and reused at least three times without considerable catalytic activity loss.
在本工作中，评估了 Ag/ZnO/CoFeO 磁性光催化剂在布洛芬（IBP）光催化降解中的性能。本研究考虑使用纯 Ag/ZnO（5%Ag）以及使用含有不同量（5、10 和 15%wt）钴铁氧体（CoFeO）的 Ag/ZnO/CoFeO 磁性催化剂。通过扫描电子显微镜（SEM）、X 射线衍射（XRD）和光声光谱对催化剂进行了表征。为了进行光催化降解反应，测试了不同浓度的布洛芬污染物溶液（10、20 和 30ppm）和不同浓度的催化剂（0.3gL、0.5gL 和 1.0gL）。研究的反应参数包括：IBP 浓度、催化剂浓度、吸附和光解、基质的影响、辐射源（太阳和人工）以及有机添加剂的影响。在光催化测试结束时，定义了最佳操作条件。考虑到降解效率和磁性分离的结果，选择最佳参数来进行研究的其他测试为：IBP 溶液浓度 10ppm、Ag/ZnO/CoFeO（5%）催化剂浓度 0.3gL 和反应介质的 pH 值 4.5。结果表明合成催化剂的磁性分离是可行的。长时间测试表明，催化剂在整个降解反应中表现出稳定性，在 300 分钟后，超过 80%的 IBP 被降解。光催化活性直接受到铁氧体负载的影响。铁氧体的名义负载越高，IBP 降解性能越低。还观察到，研究中最小量的铁氧体足以使催化剂得到回收和再利用。吸附和光解测试在 IBP 降解中没有显示出显著的结果。此外，可以验证水基质、太阳辐射的使用和添加剂（甲酸）的添加直接干扰了该过程。催化剂重复使用测试表明，它可以至少回收和再使用三次，而不会导致催化活性明显损失。
